Extracorporeal blood handling system with automatic flow control and methods of use

Abstract

Apparatus for processing blood in an extracorporeal circuit with automatic flow control is provided in which error conditions are sensed and system operation is modulated responsive to the error conditions. The apparatus includes an extracorporeal blood processing system, at least one sensor that senses the presence or absence of gas or monitors venous pressure, and a controller operably coupled to the blood processing system to selectively reduce pump speed or to reconfigure flow paths within the blood processing system responsive to the sensor output.

1. An apparatus for processing blood in an extracorporeal circuit, comprising:
 a venous line;  
 an arterial line;  
 a blood processing system having a pump, a filter having a gas collection plenum and an oxygenator, the blood processing system having an inlet to receive blood from a patient via the venous line and an outlet for reperfusing blood to the patient via the arterial line, the pump operably coupled to the filter to communicate suction to the venous line;  
 a sensor coupled to the gas collection plenum to detect the presence of air in the venous line or filter and generates an output; and  
 a controller programmed to modulate operation of a speed of the pump responsive to the output while retaining some forward flow through the arterial line to the patient.  
 
     
     
       2. The apparatus of  claim 1 , wherein the controller is programmed to reduce the speed of the pump responsive to the output. 
     
     
       3. The apparatus of  claim 2 , further comprising a valve coupled to a vacuum source, wherein the valve is configured to be selectively actuated by the controller responsive to the output of the sensor. 
     
     
       4. The apparatus of  claim 3 , wherein the controller further is responsive to duration of actuation of the valve. 
     
     
       5. The apparatus of  claim 2 , wherein the speed pump is reduced to a predetermined limit value or by a predetermined percentage. 
     
     
       6. The apparatus of  claim 2 , wherein the speed of the pump is reduced in predetermined absolute or percentage increments. 
     
     
       7. The apparatus of  claim 1 , wherein the sensor is disposed on the venous line. 
     
     
       8. The apparatus of  claim 7 , wherein the sensor monitors pressure in the venous line. 
     
     
       9. The apparatus of  claim 7 , wherein the sensor is a bubble detector. 
     
     
       10. The apparatus of  claim 1 , wherein the blood processing system further comprises a valve operably coupled to the arterial line, and the controller modulates operation of the blood processing system by changing a configuration of the valve. 
     
     
       11. The apparatus of  claim 10 , wherein the controller further modulates operation of the blood processing system by reducing a speed of the pump. 
     
     
       12. The apparatus of  claim 1 , wherein the blood processing system further comprises a recirculation line disposed between the inlet and the outlet and a valve operable coupled to the recirculation line, and the controller modulates operation of the blood processing system by changing a configuration of the valve. 
     
     
       13. The apparatus of  claim 12 , wherein the controller further modulates operation of the blood processing system by reducing a speed of the pump. 
     
     
       14. An apparatus for processing blood in an extracorporeal circuit, comprising:
 a venous line;  
 an arterial line;  
 a blood processing system including a pump, a filter having an air collection plenum and an oxygenator, the blood processing system having an inlet to receive blood from a patient via the venous line and an outlet for reperfusing blood to the patient via the arterial line;  
 a sensor operably coupled to the filter to generate an output;  
 a valve coupled to the filter to selectively remove air from the air collection plenum; and  
 a controller programmed to modulate operation of the valve and the pump responsive to the output while retaining some forward flow through the arterial line to the patient.  
 
     
     
       15. The apparatus of  claim 14 , wherein the controlled is programmed to reduce a speed of the pump responsive to the output. 
     
     
       16. The apparatus of  claim 15 , wherein the valve is coupled to a vacuum source. 
     
     
       17. The apparatus of  claim 15 , wherein the speed of the pump is reduced to a predetermined limit value or by a predetermined percentage. 
     
     
       18. The apparatus of  claim 15 , wherein the speed of the pump is reduced in predetermined absolute or percentage increments. 
     
     
       19. The apparatus of  claim 14 , wherein the controller further is responsive to duration of actuation of the valve. 
     
     
       20. The apparatus of  claim 14 , further comprising a sensor is disposed on the venous line. 
     
     
       21. The apparatus of  claim 20 , wherein the sensor is a bubble detector. 
     
     
       22. The apparatus of  claim 20 , wherein the sensor monitors pressure in the venous line. 
     
     
       23. The apparatus of  claim 14 , wherein the blood processing system further comprises a valve operable coupled to the arterial line, and the controller modulates operation of the blood processing system by changing a configuration of the valve. 
     
     
       24. The apparatus of  claim 23 , wherein the controller further modulates operation of the blood processing system by reducing a speed of the pump. 
     
     
       25. The apparatus of  claim 14 , wherein the blood processing system further comprises a recirculation line disposed between the inlet and the outlet and a valve operable coupled to the recirculation line, and the controller modulates operation of the blood processing system by changing a configuration of the valve. 
     
     
       26. The apparatus of  claim 25 , wherein the controller further modulates operation of the blood processing system by reducing a speed of the pump.